Host: The Japan Society of Mechanical Engineers
Name : Dynamics and Design Conference 2016
Date : August 23, 2016 - August 26, 2016
The nonlinear liquid motion in a partially filled rectangular tank with a core barrel is investigated. Basic equations are derived by employing the variational principle. Equations of motion governing nonlinear surface oscillations are derived by applying the Galerkin’s method to basic equations. Admissible functions are assumed to be represented by combining the modes of vibration. Because of complicated shape tank like a rectangular tank with a core barrel, the modes of vibration and the natural frequencies are not obtained by analytical method. Therefore, they are calculated by using the finite elements method. Occurrence condition of internal resonance were considered. In the case of a complicated shape tank, since the nonlinear coupling between the modes become vague, it is difficult to predict the internal resonant modes. By considering the coefficients in the derived nonlinear equations of motion of nonlinear coupling modes, an index to predict the mode of which amplitude may become large by internal resonance is proposed. Experiments were carried out at the condition when the nonlinear liquid sloshing occurs. The occurrence of the internal resonance was confirmed by the experimental results. It is shown that the amplitude of the predicted internal resonant mode become large in both analytical and experimental results. Effectiveness of the analysis and validity of the proposed index are verified.
